The largest-ever trial of a four-day working week has concluded with resounding results: the vast majority of participating companies plan to keep the shorter schedule permanently. The six-month pilot, which ran from June to December 2022 across the United Kingdom, involved 61 companies and nearly 2,900 employees. Researchers from the University of Cambridge, Boston College, and the think tank Autonomy found that productivity did not suffer, while employee well-being improved significantly.
The study was spearheaded by the non-profit organization 4 Day Week Global, which advocates for a 100-80-100 model: 100 percent of the pay for 80 percent of the time, in exchange for a commitment to maintain 100 percent productivity. The trial required companies to reduce working hours without cutting salaries.
Data Shows Benefits Beyond the Break
The results paint a compelling picture. According to the final report, 39 percent of employees reported feeling less stressed, and 71 percent had reduced levels of burnout at the end of the trial compared to the start. Anxiety, fatigue, and sleep issues also declined.
Perhaps more striking for business owners: revenue remained largely stable. Across the 61 firms, revenue actually rose by an average of 1.4 percent during the trial, weighted by company size. When compared to the same period in previous years, revenue growth was a more dramatic 35 percent.
“This is a major breakthrough for the movement towards a shorter working week,” said Juliet Schor, a lead researcher and Professor of Sociology at Boston College. “The results show that the four-day week works in a wide variety of sectors and for companies of very different sizes.”
Human Impact: More Than a Long Weekend
For many workers, the extra day off was transformative. Joe Ryle, director of the 4 Day Week Campaign in the UK, noted that employees reported spending more time with family, pursuing hobbies, and even getting routine healthcare they had previously postponed.
“One mother told us she now had time to take her child to swimming lessons on a Friday,” Ryle said. “A man in his fifties said he finally had the energy to start running again. These are not just perks; they are fundamental improvements to quality of life.”
The trial did reveal challenges. Many employees reported working more intensely, compressing five days of labor into four. Some companies struggled with customer coverage, as the entire office was closed on Fridays. Managers in firms with traditional, presenteeist cultures found it harder to adjust than those focusing purely on output.
A Global Shift Gaining Momentum
The UK pilot is part of a broader, global wave. Similar trials have taken place in Iceland—where the vast majority of workers now have a right to a shorter week—as well as in Spain, New Zealand, and the United States. In 2023, a separate trial in Portugal involving 41 companies showed analogous gains in sleep quality and personal relationships.
Critics, however, remain cautious. They argue that not all sectors—particularly hospitality, healthcare, and education—can easily implement a four-day schedule without significant government investment or hiring.
What Comes Next?
The movement appears to be gaining mainstream political traction. In the UK, the Labour Party has floated exploring a shorter working week as part of a broader “right to disconnect” law. Meanwhile, Belgium made headlines in 2022 by granting workers the legal right to request a four-day week—though it is unpaid for the fifth day.
For companies considering the switch, experts recommend starting with a pilot program, clearly defining performance metrics, and involving staff in the redesign of workflows.
“The four-day week is not a panacea, but it is an evidence-based tool to improve both business outcomes and human well-being,” said Schor. “The debate is no longer about if it can work, but how to scale it.”
As millions of workers globally reassess their relationship with work—accelerated by the pandemic—the four-day week is emerging not as a fringe experiment, but as a plausible blueprint for the future of employment.
